Out of curiosity, what made you want to upgrade so early? Microsoft made an announcement stating that while RTM copies are availble, there's going to be a likely large bug-fixing patch on actual launch. I considered doing it myself until I saw that but I still would've done a disk-level backup even on release much less RTM just in case. Took me ages to setup all the development requirements for this thing.
I'm merely asking as I really haven't followed the change list and the small parts I saw didn't seem relevant to what I use it for. Have no plans to get a Surface which seems to be a lot of the changes and the rest only really towards the Modern UI which after even like 8 months maybe, I still have yet to install a single Modern app 
We keep making development easier and easier and despite all that, I think maybe 5% of the developers I meet even know what the stack and heap are or are used for. It's one abstraction layer on top of another so its no wonder we need to keep increasing CPU speeds not to mention it's pretty hard to program with performance in mind when you haven't a clue how the engine interpreting your code works or the OS underneath it.